Sunday, January 27, 2008

Photos from CERN

As I mentioned a couple of posts back, we were lucky enough to go the 100m down into the chamber for the CMS detector. I got a few pictures while we were there.

First of all, on the surface before going into the cavern and indeed all around the CERN sites you see huge gas tanks. These tanks are for storing helium. The detectors and accelerator have to be cooled to just above absolute zero (there are superconducting magnets for the accelerator which only work at very low temperatures). If there is a problem with any of the components they may have to be taken apart, or at least looked at in detail. In order to do this, the helium will be released and the parts will warm back up. CERN has the largest supply of helium in the world and this is both expensive stuff and not easy to produce. It is still being produced now in order that they have a large enough supply. So, when you release the helium you want to store it somewhere, not just let it off into the atmosphere, and that is what these enormous tanks are for. The circumference of the tanks is, I guess, around 2 or 3 meters.
LHC helium tanks
100m down into the cavern and we were lucky enough to see the last two pieces of the CMS detector being readied to slot into place. The following panorama is from 6 shots, which don't go together perfectly, but give a pretty good impression of the complexity of the detector:
CMS detector panorama
The largest component of the CMS detector weighs in at 2000 tonnes. Your average crane cannot carry this sort of weight and so in order to lower it into the cavern they had to construct a specially designed pulley system. The two towers on top of the CMS building housed the wheels for this pulley. In the background of this picture is Mont Blanc:
CMS and Mont Blanc
Mont Blanc can be seen more clearly in this picture which I took as we were taking the bus to the site. The new polarising filter for my camera works very well at removing the reflections from the glass in the bus. the extreme blue in the sky in the picture of the helium tanks also comes from using a polarising filter which helps to remove any haze:
Mont Blanc
See here for a couple more from the detector.


Luca said...

Will they start soon? I'm tired of sitting at talks, that describe how wonderful the results will be, and how shaken our view of the world will emerge.

Anyway. Thanks for sharing. The CMS picture was indeed pretty impressive, and I was wondering whether you got a fish-eye for yourself.

Will you attend Strings this year?

Unknown said...

Hi Luca,

Yes, the machine is due to be turned on some time around the middle of 2008, of course they will start with low luminosities and will take some time to actually learn how to use the detectors. It's most likely that we will have the first real results some time at the beginning of 2009 but if there is something really exotic with a clear signature then we may have the results even sooner.

I should be at strings if I'm not giving some talks in Asia at the time. Will you be going?

No fish-eye for me. I got a piece of software called ArcSoft Panorama maker which is not that expensive but, in my opinion, the best panorama program I've seen.

All the best,


Luca said...

Hi Jon,

good to hear that that big loop in France and Switzerland will start soon! To be on the realistic side, I doubt we should see anything exotic at the beginning of '09.

I'll not be at strings this year. I'm planning to take a (real) vacation in June, and with the moving and stuff I don't have the time for it. I'll try to go to Rome next year.